get file path on custom (node) submit handler

Hi,

Is there a way to get the filefield path on during node submit (save process)?
I need to write a text file in the same directory as my files when I submit a node with file field and custom file path.

I was hoping to use hook_form_submit_handler($form, &$form_state) but $form_state['values'] does't include the custom path only private://files
Can I find the custom path during my submit handler? Where would you suggest writing the code to write a txt file (including submitted node field values) to same path as the files saved files?

Any help appreciated!